SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '746c6587a2a3ed0b1314f91c95b0fcee1a7852916855c5d4cefc578ec75adb19' 
  AND token = 'ssKdJqg6mkpRfl6J/I+SGosdQ3Zqfh6GLJ7pic3Bqcw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}